Month: April 2018

5 biggest threats to our oceans – and what we can do about them

Oceans cover more than two-thirds of our planet and give us food, energy and other resources. But worldwide, this fantastic underwater world is in danger. Is there still time to prevent the worst?

Surfing, boating, long walks on the beach – yes, we love our oceans. And yet, we treat them horribly, even though we need them to survive.

DW takes a closer look at the five biggest man-made threats to these massive bodies of water – and why we should try desperately to save the oceans while we still have a chance.

1. Depleted fish stocks

Eating fish and seafood is good for our health and many people worldwide, particularly in low-income countries, rely on these important sources of protein. In the past, the number of fish and other sea creatures caught by humans could be replenished through natural reproduction. Today, however, we take out more than what nature can deliver.

Around 30 percent of global fish stocks are overexploited or have already collapsed; 58 percent are at their limit.

The countries with the largest marine capture rates in 2015 were China, Indonesia and the US. In total, 23 countries are responsible for 80 percent of the world’s fish and seafood production – most of them high-income countries.

A growing human population needs plenty of fish – too many?

Conventional aquaculture, often seen as a solution, actually makes matters even worse. This industrial mass fish farming, partly in cages in the oceans, uses up huge amounts of seafood as feeding material.

Aquaculture farms also pollute their surrounding areas with excrement and facilitate the spread of fish diseases.

More rigorous fishing quotas and better fishery management could help. Fish stocks can recover within decades or even years, but action needs to be taken soon before some species are critically endangered or even lost forever.

And yes: limiting the amount of fish and seafood we eat to a reasonable level and backing away from eating endangered species would also help.

2. Ocean acidification

Carbon dioxide emissions have increased significantly since the beginning of industrialization in the 19th century. But the concentration of CO2 in the atmosphere has only risen by around 40 percent.

That’s because much of the CO2 ends up in the oceans, as the gas dissolves in water. Oceans, therefore, help slow global warming – but that help comes at a price.

Why are oceans becoming more acidic?

When CO2 dissolves in water it increases ocean acidity, leading to a drop in pH, the scale used to measure acidity or basicity. In 1870, the average pH of seawater was 8.2; today, it’s at 8.1. By 2100, that value is predicted to even become more acidic, dropping to 7.7.

Though it appears to be only a minor change, that drop of 0.1 corresponds to a 150 percent increase in acidity. Many sea creatures aren’t able to cope with such an extreme change, and will stop reproducing and eventually die out.

In 2005, oyster farms along the Californian coast were forced to close because seawater there had become too acidic for oyster larvae. They died – and with them a whole industry.

Mollusks, such as mussels, are particularly sensitive to a drop in pH. But fish species can suffer as well. In 2015, a study published in the scientific journal Global Change Biology showed that acidification might even have a detrimental effect on plankton, tiny marine organisms that are a crucial food source for many fish and mammals.

Unfortunately, there is only one way to stop ocean acidification, and that’s to reduce the amount of CO2 emissions – as soon as possible.

WHAT HAPPENS WHEN OCEAN TEMPERATURES RISE?

Atlantis 2.0

As global warming speeds up, so does the rise in sea levels. While 2004 to 2010 saw oceans rise by about 15 millimeters in total, this value doubled for 2010 to 2016. Tropical regions in the western Pacific are especially affected, threatening many of the coastal areas and low-lying islands with submersion by the end of the century.

3. A warming world

The oceans not only store CO2 – they also store heat. In fact, they absorb more than 93 percent of the heat generated by man-made CO2 emissions, warming the water.

Between 1900 and 2008, seawater surface temperature rose by 0.62 Celsius (1.12 Fahrenheit) on average. In some areas in the Western Pacific Ocean, that increase was as much as 2.1 Celsius.

Warming is major problem for many underwater organisms, and in particular corals.

A coral, before and after bleaching

Corals are creatures that form a hard exoskeleton out of calcium carbonate. Inside, they harbor colorful photosynthetic algae. When the surrounding water gets too warm, corals expel the algae and finally starve to death, an event called coral bleaching.

Only a reduction in CO2 emissions can prevent seawater temperatures from any further increases.

Meanwhile, researchers are also working on breeding corals that are more resilient to warmer water temperatures, or learning how to boost their sexual reproduction. Hopefully, these efforts might help coral reefs survive in a warming world.

The oceans were once a big waste dump for sailors, cruise ships and coastal towns. For some, they still are. Even though our attitude toward the sea has changed, there is still an awful lot of trash building up in the oceans.

Five huge trash vortexes have formed in the world’s oceans, areas where the currents trap trillions of pieces of plastic and other debris. These garbage patches are estimated to measure between 700,000 and 15 million square kilometers (up to 5.7 million square miles).

Plastic waste washes ashore around the world, including here in Ghana

But as much as 99 percent of plastic waste never reaches these vortexes. A lot ends up on shorelines, polluting coasts and putting seabirds, turtles and other wildlife in danger.

Most of the waste, though, decomposes or is broken up into tiny pieces – microplastics, distributing themselves on the ocean floor, in sea ice at the poles and even in fish who ingest them as food.

And there are other pollutants as well, like nitrate and phosphate from industrial farms that enter the oceans via rivers. These substances cause algae to bloom. When algae die, they are decomposed by bacteria, which reduces the water’s oxygen content so that nothing else can grow there.

Industrial wastewater and emissions also add dangerous metals and chemicals to the oceans, including lead, mercury and persistent organic pollutants. The latter accumulate in the fat of whales, sharks and other animals.

Is there a solution to this mess?

The Ocean Cleanup, a Dutch foundation, has announced a plan to start extracting plastic from an area known as the Great Pacific garbage patch in 2018 using a floating system developed for this purpose.

Apart from that, efforts to reduce plastic waste and implement stricter rules concerning wastewater treatment are necessary around the globe.

FIGHTING THE PLASTIC FLOOD

Tons of trash

At least 8 million tons of plastic waste ends up in the world’s oceans every year, according to a report by the Ellen MacArthur Foundation. The report warns plastic trash will outweigh fish by 2050 unless drastic action is taken. Much of the floating trash collects in several large ocean vortices far from land. Beaches, like this one on Midway Island in the remote Pacific Ocean, also suffer.

5. Buried treasure

You might think that our oceans have already seen enough exploitation. But the big rush may be yet to come.

Deep in the oceans, valuable natural resources are waiting to be uncovered. One example is manganese nodules, rocks on the seafloor composed of iron and manganese hydroxide. Manganese is used to produce industrial metal alloys, in particular stainless steel.

Manganese nodules and other precious minerals line the ocean floor

Experts estimate there are more than 7 billion tons of manganese in the oceans, more than in reserves on land.

Many countries have already secured claims on the seafloor, areas where they plan to begin mining operations as soon as the process is allowed and becomes economically viable.

Other precious metals like cobalt, nickel, thallium and rare earth elements are also known to exist down below, ready for extraction. But research shows that such metallic nodule fields are hot spots of biodiversity.

Last year, researchers discovered a “ghostlike” octopus living close to these nodules which they called Casper. Mining operations could dramatically affect these delicate ecosystems.

HOW TO CHANGE A FLAT TIRE

Knowing how to change a tire is a necessary skill for all drivers. If you rely on a cell phone to save you in a roadside emergency, there’s always that chance you will forget to charge it, be out of range, or leave it at home. Flat tires can happen anywhere, and a cell phone is no substitute for knowing how to change a flat tire.

Thankfully, changing a tire isn’t all that hard! Just adhere to the following guidelines to be prepared in case you have a flat.

ITEMS YOU’LL NEED TO FIX A FLAT TIRE

These items should have come with your vehicle:

Jack

Lug wrench

Fully inflated spare tire

Vehicle owner’s manual

If you have misplaced any of these items, or if your car did not come with these items, you should purchase new ones right away. And be sure you’re regularly inflating the spare tire to your vehicle manufacturer’s recommended PSI. You should check the spare’s air pressure every time you check your other tires. Remember to check pressure every month and before long trips or carrying extra load.

Here are some items that don’t come with your vehicle but that you should stow in your trunk or glove box in case you have to change a flat tire:

Flashlight with working batteries

Rain poncho

Small cut of 2″x6” wood to secure the jack

Gloves

Wheel wedges

HOW TO CHANGE TIRES

1. FIND A SAFE LOCATION

As soon as you realize you have a flat tire, do not abruptly brake or turn. Slowly reduce speed and scan your surroundings for a level, straight stretch of road with a wide shoulder. An empty parking lot would be an ideal place. Level ground is good because it will prevent your vehicle from rolling. Also, straight stretches of road are better than curves because oncoming traffic is more likely to see you.

Never attempt to change your tire on a narrow shoulder near oncoming traffic. Keep moving (slowly) until you find a safer spot. While driving on a flat risks ruining your rim, replacing a rim is better than being hit by an inattentive driver.

Make sure to consult your owner’s manual and review their specific steps on how to change a flat tire for your vehicle

2. TURN ON YOUR HAZARD LIGHTS

Your hazard lights or “flashers” will help other drivers see you on the side of the road. To avoid an accident, turn them on as soon as you realize you need to pull over.

3. APPLY THE PARKING BRAKE

Once stopped, always use the parking brake when preparing to replace a flat tire. This will minimize the possibility of your vehicle rolling.

4. APPLY WHEEL WEDGES

Wheel wedges go in front of or behind the tires to further ensure the vehicle doesn’t roll while you fix the flat tire. If you’re changing a rear tire, place these in front of the front tires. If your flat tire is at the front, put the wheel wedges behind the rear tires.

Bricks or large stones will work just as well as “real” wheel wedges. Just be sure they’re large enough to stop the car from rolling.

5. REMOVE THE HUBCAP OR WHEEL COVER

If your vehicle has a hubcap covering the lug nuts, it’s easier to remove the hubcap before lifting the vehicle with the jack. If your lug nuts are exposed, you can skip ahead to Step 6.

Use the flat end of your lug wrench to remove the hubcap. This will work for most vehicles, but some hubcaps need a different tool to come off. Consult your owner’s manual for proper hubcap or wheel cover removal procedures.

6. LOOSEN THE LUG NUTS

Using the lug wrench, turn the lug nuts counterclockwise until you break their resistance. You may have to use force, and that’s ok. Use your foot or all of your body weight if necessary.

Loosen the lug nuts about ¼ to ½ of a turn, but don’t remove them completely yet. Save that for when it’s time to remove your tire/wheel from the vehicle.

7. PLACE THE JACK UNDER THE VEHICLE

The right place for the jack is usually beneath the vehicle frame alongside the tire that’s flat. Many vehicle frames have molded plastic on the bottom with a cleared area of exposed metal specifically for the jack. To safely lift and avoid damage to the vehicle, follow the instructions for jack placement in your vehicle owner’s manual.

8. RAISE THE VEHICLE WITH THE JACK

To prevent the jack from settling under the weight of your vehicle and coming off balance, place a small cut of 2×6” wood beneath it before attempting to raise your vehicle. This tactic is especially helpful on asphalt.

With the jack properly positioned, raise the vehicle until the flat tire is about six inches above the ground.

Never put any part of your body under the vehicle during or after raising the vehicle with the jack.

9. UNSCREW THE LUG NUTS

Now it’s time to remove the lug nuts all the way. Since you’ve already loosened them, you should be able to unscrew them mostly by hand.

10. REMOVE THE FLAT TIRE

Gripping the tire by the treads, pull it gently toward you until it’s completely free from the hub behind it. Set it on its side so that it doesn’t roll away.

11. MOUNT THE SPARE TIRE ON THE LUG BOLTS

Now place the spare on the hub by lining up the rim with the lug bolts. Push gently until the lug bolts show through the rim.

12. TIGHTEN THE LUG NUTS BY HAND

Put the lug nuts back on the lug bolts and tighten them all the way by hand. Once they are all on, check each one again, tightening as much as possible. You will tighten them with the wrench after lowering the vehicle to the ground.

13. LOWER THE VEHICLE AND TIGHTEN THE LUG NUTS AGAIN

Use the jack to lower the vehicle so that the spare tire is resting on the ground but the full weight of the vehicle isn’t fully on the tire. At this point, you should tighten the lug nuts with the wrench, turning clockwise, as much as you can. Push down on the lug wrench with the full weight of your body.

14. LOWER THE VEHICLE COMPLETELY

Bring the vehicle all the way to the ground and remove the jack. Give the lug nuts another pull with the wrench to ensure they’re as tight as possible.

15. REPLACE THE HUBCAP

If the hubcap you took from the flat tire will fit your spare, put it in place the same way you removed it initially. If it doesn’t fit, stow it away with the tire when you stow your equipment.

16. STOW ALL EQUIPMENT

You have before you a jack, a lug wrench, wheel wedges, your flat tire, and possibly a hubcap. Don’t forget to put all of them in your vehicle before driving away.

17. CHECK THE PRESSURE IN THE SPARE TIRE

You should check the tire pressure of the spare tire to make sure that it is safe to drive on. “T-Type” temporary spares, also called “mini-spares,” require 60 psi (420 kPa). If the tire needs pressure, drive (slowly) to a service station immediately.

18. TAKE YOUR FLAT TIRE TO A TECHNICIAN

Temporary spare tires aren’t made to drive long distances or at high speeds, so drive cautiously until you’re able to visit a tire technician. A professional should be able to determine whether your tire needs a repair or if it’s time to replace it.

HOW LONG DOES IT TAKE TO FIX A FLAT TIRE?

Aside from taking your tire to a professional, the above procedure shouldn’t take more than 15 to 30 minutes to change a tire. Just be sure you don’t leave out any steps.

It’s beneficial practice changing a tire in your garage or driveway to ensure you’re ready to handle this situation if it ever happens to you.

A FEW MORE TIPS ON CHANGING TIRES

Knowing how to fix a flat tire is great, but regular tire maintenance is even more important. In addition to reviewing this guide regularly, remember to do the following:

Keep your tires properly inflated

Rotate your tires according to the manufacturer’s guidelines

Monitor for tread wear

All of these precautions will extend the life of your tires and reduce the likelihood of a flat. While there’s no way to prevent flat tires completely, proper care can improve performance and ensure your tires last as long as possible.

Why do we have so many wildflowers along the highways? Credit the Texas Department of Transportation. The agency says: “Shortly after the Texas Highway Department was organized in 1917, officials noted that wildflowers were among the first vegetation to reappear at roadside cuts and fills. In 1932, the department hired Jac Gubbels, its first landscape architect, to maintain, preserve and encourage wildflowers and other native plants along rights of way. By 1934, department rules delayed all mowing, unless essential for safety, until spring and early summer wildflower seasons were over. This practice has stayed in place for more than 60 years and has expanded into today’s full-scale vegetation management system.” TxDOT buys and sows about 30,000 pounds of wildflower seed each year.

CREDIT WAYNE WEATHERRED — FLICKR.COM/PHOTOS/STIMPYJCAT/

3. We create family memories in the bluebonnet fields

Snapping pictures of the family in a field of bluebonnets: It’s an iconic springtime image in Texas. And Texans have done it for generations.

Historian Jack Maguire once wrote: “It’s not only the state flower but also a kind of floral trademark almost as well known to outsiders as cowboy boots and the Stetson hat.” He also said: “The bluebonnet is to Texas what the shamrock is to Ireland, the cherry blossom to Japan, the lily to France, the rose to England and the tulip to Holland.”

Listen to the KERA Radio story: Travel the bluebonnet trails in Ennis and find out why people in the Ellis County town are so fanatical about the state flower.

7. But there’s competition for Bluebonnet Central

Then there’s Chappell Hill, which earned the title “Official State of Texas Bluebonnet Festival.” It, too, is proud of its bluebonnets. Its 50th annual Bluebonnet Festival takes place Saturday and Sunday. Chappell Hill, which calls itself “the heart of Bluebonnet Country,” is located halfway between Houston and Austin on Hwy. 290.

Can you ever get tired of looking at bluebonnets? Nope.

CREDIT RICHARD A MCMILLIN — SHUTTERSTOCK.COM/GALLERY-1034824P1.HTML

8. Meet a flower scholar

PerriAngela Wickham, a bluebonnet addict, posts regular bluebonnet updates on her website, bluebonnetlove.com. She drives around Texas roadsides on spring weekends and spreads the word on the best places to admire the state’s favorite flower. The catch: She lives near Washington, D.C., and flies back and forth to Texas a few times each spring.

9. A bluebonnet’s brilliant life cycle: Germination is key

Bluebonnets germinate in the fall, when they benefit the most from a drink of water. So fall rainfall is critical. But winter rains help, too. The snow helps insulate the plants. In Ellis County, Ennis Garden Club members start to monitor the plants after Christmas. Then, by February and March, people start to ask: “How are the bluebonnets? When will they peak?” In North Texas, they peak in mid to late April. The Lady Bird Johnson Wildflower Center explains what happens next: “Around mid-May, they form a seedpod, which is green at first but turns yellow and then brown. Sometime between the yellow and brown form of the seedpod, the seeds mature. The seedpods pop open, releasing the small, hard seeds.” Many say the bluebonnets make pop-pop-pop-ing sounds.

10. Germination 411

Texas A&M AgriLife Extension dives into germination: “Only a small percentage of the seed germinates during the first season after planting. This delayed germination ensures species survival during periods of adverse growing conditions such as prolonged drought. … To ensure rapid, high percentage germination, the bluebonnet seed has to be treated to remove inhibiting properties of the seed coat which otherwise prevent water uptake and the initiation of growth. This process of seed treatment is referred to as scarification. Seed which has been properly scarified will germinate within 10 days after planting in a moist soil.”

A maroon version of the state flower that’s sprouted in the shadow of the University of Texas Tower in Austin has some wondering if it’s the work of Aggie pranksters. Flower beds containing brightly colored bluebonnets are now home to a variant known as Alamo Fire, which is a shade of maroon. (The Texas A&M colors are maroon and white.) There’s speculation in the land of the Longhorns that Aggies are responsible for sprinkling Alamo Fire seeds on the UT campus, the Associated Press reports. Texas A&M horticulturists developed the maroon variety in the 1980s in an attempt to plant a floral Texas flag in honor of the state’s sesquicentennial. Texas A&M professor and horticulturist Doug Welsh says the recessive maroon hue will recede over time to the bluebonnet’s dominant shade of indigo.

10 Important Things You Should Check On Your Car Regularly

Your car gets you safely everywhere you want to go, but it requires that you take good care of it in order to keep running right. Taking care of your car is as important for keeping you on the road and getting where you want to go as it is for your safety. Some of these simple maintenance issues can actually result in an accident or injuries. Take the time to make sure these 10 things are checked regularly and maintained as needed and avoid a potential accident or claim.

The Oil
The oil in your car keeps everything running smoothly, and your car can’t run without the right level of oil. You can check your oil level by yourself easily by simply pulling out the dipstick and seeing where the oil level is. You should take your car in for an oil change on a regular basis as recommended by your vehicle manufacturer or mechanic. Oil changes are one of the most basic car maintenance procedures, and checking your oil an easy way to catch leaks.

The Tire Pressure
A tire pressure gauge is an affordable and easy to use tool that can prevent a flat tire or worse. Tires that are improperly inflated can cause blowouts that lead to accidents. They can also find you stranded on the side of the road. Additionally, the wrong level of inflation affects your fuel efficiency. It’s important to check them regularly and also be aware that the right tire pressure changes based on the outside temperature. Check with the tire manufacturer for the right pressure.

The Brakes
Don’t wait for that screeching sound that tells you the brake pads are getting old. Having your brakes checked regularly by a pro keeps your car safe and on the road. You depend on your brakes to stop your car and prevent an accident, so don’t take them for granted. It’s best to have a pro check your brakes as part of regular maintenance.

The Power Steering Fluid
If you have ever driven a car without power steering, then you know how important it is to check this fluid. Without it your power steering could fail, making it harder to control your car. Like your oil, you can check and refill this one yourself, so make it a habit.

The Alignment
While you will probably notice if your alignment is getting bad, it’s a good idea to have it looked over regularly, as it impacts the way your car handles on the road. Get your alignment adjusted as needed to ensure your car will steer and react the way you want it to when you need to move quickly.

The Antifreeze/Coolant
In Canadian winters, you will need to make sure that you have enough antifreeze in your car to make sure it can run properly. Cold temperatures are hard on your car. On the reverse side of that coin, coolant is also an important fluid to check on your car. Keeping your car running smoothly relies on the right levels of the fluids it needs.

The Tire Tread
It’s not just the pressure in your tires that matters. Your tires depend on the tread to give you traction on the road, and it’s especially important in slippery conditions. Look for signs of wear in your tires – and also look for any bulges or odd lumps that could indicate a problem. Low tread or bulges in the tires can cause slipping or a blowout on the road, and lead to an accident.

The Air Filter
A clogged air filter will cost you in fuel consumption, and it’s bad for the car as well. It costs very little to get it checked and replaced as needed, so make it a regular part of your car maintenance routine. Most places will check it for you when they change your oil free of charge.

The Transmission Fluid
Your transmission failing while driving is not something you ever want to experience. Make sure that the transmission fluid is always at a good level and is changed periodically to make sure your car can shift smoothly and keep you in control of the car at all times.

The Lights – All of Them
Having any of the lights on your car not functioning properly is dangerous. Be sure to check your turn signals, brake lights, reverse lights and of course your headlights on a regular basis. Although you are likely to catch a headlight that is out, you could easily miss a brake like or taillight that doesn’t function right. These things are vital to letting other vehicles know what you are doing or about to do – and preventing accidents. You could also get a ticket for having a light out, which could mean higher car insurance rates.

Keep your car in good running condition and it will keep you safe and in control on the road. It takes a short amount of time to check these important functions, but can save money, fuel, and even lives in the long run. Make sure the functions of your car aren’t the only thing you’re checking.

10 INTERESTING FACTS ABOUT EARTH

Planet Earth. That shiny blue marble that has fascinated humanity since they first began to walk across its surface. And why shouldn’t it fascinate us? In addition to being our home and the place where life as we know it originated, it remains the only planet we know of where life thrives. And over the course of the past few centuries, we have learned much about Earth, which has only deepened our fascination with it.

But how much does the average person really know about the planet Earth? You’ve lived on Planet Earth all of your life, but how much do you really know about the ground underneath your feet? You probably have lots of interesting facts rattling around in your brain, but here are 10 more interesting facts about Earth that you may, or may not know.

1. Plate Tectonics Keep the Planet Comfortable:

Earth is the only planet in the Solar System with plate tectonics. Basically, the outer crust of the Earth is broken up into regions known as tectonic plates. These are floating on top of the magma interior of the Earth and can move against one another. When two plates collide, one plate will subduct (go underneath another), and where they pull apart, they will allow fresh crust to form.

The Earth’s Tectonic Plates. Credit: msnucleus.org

This process is very important, and for a number of reasons. Not only does it lead to tectonic resurfacing and geological activity (i.e. earthquakes, volcanic eruptions, mountain-building, and oceanic trench formation), it is also intrinsic to the carbon cycle. When microscopic plants in the ocean die, they fall to the bottom of the ocean.

Over long periods of time, the remnants of this life, rich in carbon, are carried back into the interior of the Earth and recycled. This pulls carbon out of the atmosphere, which makes sure we don’t suffer a runaway greenhouse effect, which is what happened on Venus. Without the action of plate tectonics, there would be no way to recycle this carbon, and the Earth would become an overheated, hellish place.

2. Earth is Almost a Sphere:

Many people tend to think that the Earth is a sphere. In fact, between the 6th cenury BCE and the modern era, this remained the scientific consensus. But thanks to modern astronomy and space travel, scientists have since come to understand that the Earth is actually shaped like a flattened sphere (aka. an oblate spheroid).

This shape is similar to a sphere, but where the poles are flattened and the equator bulges. In the case of the Earth, this bulge is due to our planet’s rotation. This means that the measurement from pole to pole is about 43 km less than the diameter of Earth across the equator. Even though the tallest mountain on Earth is Mount Everest, the feature that’s furthest from the center of the Earth is actually Mount Chimborazo in Ecuador.

The Earth’s layers, showing the Inner and Outer Core, the Mantle, and Crust. Credit: discovermagazine.com

3. Earth is Mostly Iron, Oxygen and Silicon:

If you could separate the Earth out into piles of material, you’d get 32.1 % iron, 30.1% oxygen, 15.1% silicon, and 13.9% magnesium. Of course, most of this iron is actually located at the core of the Earth. If you could actually get down and sample the core, it would be 88% iron. And if you sampled the Earth’s crust, you’d find that 47% of it is oxygen.

When astronauts first went into the space, they looked back at the Earth with human eyes for the first time. Based on their observations, the Earth acquired the nickname the “Blue Planet:. And it’s no surprise, seeing as how 70% of our planet is covered with oceans. The remaining 30% is the solid crust that is located above sea level, hence why it is called the “continental crust”.

5. The Earth’s Atmosphere Extends to a Distance of 10,000 km:

Earth’s atmosphere is thickest within the first 50 km from the surface or so, but it actually reaches out to about 10,000 km into space. It is made up of five main layers – the Troposphere, the Stratosphere, the Mesosphere, the Thermosphere, and the Exosphere. As a rule, air pressure and density decrease the higher one goes into the atmosphere and the farther one is from the surface.

Earth, as viewed from the cabin of the Apollo 11 spacecraft. Credit: NASA

The bulk of the Earth’s atmosphere is down near the Earth itself. In fact, 75% of the Earth’s atmosphere is contained within the first 11 km above the planet’s surface. However, the outermost layer (the Exosphere) is the largest, extending from the exobase – located at the top of the thermosphere at an altitude of about 700 km above sea level – to about 10,000 km (6,200 mi). The exosphere merges with the emptiness of outer space, where there is no atmosphere.

The exosphere is mainly composed of extremely low densities of hydrogen, helium and several heavier molecules – including nitrogen, oxygen and carbon dioxide. The atoms and molecules are so far apart that the exosphere no longer behaves like a gas, and the particles constantly escape into space. These free-moving particles follow ballistic trajectories and may migrate in and out of the magnetosphere or with the solar wind.

6. The Earth’s Molten Iron Core Creates a Magnetic Field:

The Earth is like a great big magnet, with poles at the top and bottom near to the actual geographic poles. The magnetic field it creates extends thousands of kilometers out from the surface of the Earth – forming a region called the “magnetosphere“. Scientists think that this magnetic field is generated by the molten outer core of the Earth, where heat creates convection motions of conducting materials to generate electric currents.

Artist’s impression of the Earth’s protective magnetic field and the dynamo effect in its core that gives rise to it. Credit: ESA/ATG medialab

Be grateful for the magnetosphere. Without it, particles from the Sun’s solar wind would hit the Earth directly, exposing the surface of the planet to significant amounts of radiation. Instead, the magnetosphere channels the solar wind around the Earth, protecting us from harm. Scientists have also theorized that Mars’ thin atmosphere is due to it having a weak magnetosphere compared to Earth’s, which allowed solar wind to slowly strip it away.

7. Earth Doesn’t Take 24 Hours to Rotate on its Axis:

It actually takes 23 hours, 56 minutes and 4 seconds for the Earth to rotate once completely on its axis, which astronomers refer to as a Sidereal Day. Now wait a second, doesn’t that mean that a day is 4 minutes shorter than we think it is? You’d think that this time would add up, day by day, and within a few months, day would be night, and night would be day.

But remember that the Earth orbits around the Sun. Every day, the Sun moves compared to the background stars by about 1° – about the size of the Moon in the sky. And so, if you add up that little motion from the Sun that we see because the Earth is orbiting around it, as well as the rotation on its axis, you get a total of 24 hours.

This is what is known as a Solar Day, which – contrary to a Sidereal Day – is the amount of time it takes the Sun to return to the same place in the sky. Knowing the difference between the two is to know the difference between how long it takes the stars to show up in the same spot in the sky, and the it takes for the sun to rise and set once.

8. A year on Earth isn’t 365 days:

It’s actually 365.2564 days. It’s this extra .2564 days that creates the need for a Leap Year once ever four years. That’s why we tack on an extra day in February every four years – 2004, 2008, 2012, etc. The exceptions to this rule is if the year in question is divisible by 100 (1900, 2100, etc), unless it divisible by 400 (1600, 2000, etc).

9. Earth has 1 Moon and 2 Co-Orbital Satellites:

As you’re probably aware, Earth has 1 moon (aka. The Moon). Plenty is known about this body and we have written many articles about it, so we won’t go into much detail there. But did you know there are 2 additional asteroids locked into a co-orbital orbits with Earth? They’re called 3753 Cruithne and 2002 AA29, which are part of a larger population of asteroids known as Near-Earth Objects (NEOs).

The asteroid known as 3753 Cruithne measures 5 km across, and is sometimes called “Earth’s second moon”. It doesn’t actually orbit the Earth, but has a synchronized orbit with our home planet. It also has an orbit that makes it look like it’s following the Earth in orbit, but it’s actually following its own, distinct path around the Sun.

Meanwhile, 2002 AA29 is only 60 meters across and makes a horseshoe orbit around the Earth that brings it close to the planet every 95 years. In about 600 years, it will appear to circle Earth in a quasi-satellite orbit. Scientists have suggested that it might make a good target for a space exploration mission.

10. Earth is the Only Planet Known to Have Life:

We’ve discovered past evidence of water and organic molecules on Mars, and the building blocks of life on Saturn’s moon Titan. We can see amino acids in nebulae in deep space. And scientists have speculated about the possible existence of life beneath the icy crust of Jupiter’s moon Europa and Saturn’s moon Titan. But Earth is the only place life has actually been discovered.

But if there is life on other planets, scientists are building the experiments that will help find it. For instance, NASA just announced the creation of the Nexus for Exoplanet System Science (NExSS), which will spend the coming years going through the data sent back by the Kepler space telescope (and other missions that have yet to be launched) for signs of life on extra-solar planets.

Giant radio dishes are currently scan distant stars, listening for the characteristic signals of intelligent life reaching out across interstellar space. And newer space telescopes, such as NASA’s James Webb Telescope, the Transiting Exoplanet Survey Satellite (TESS), and the European Space Agency’s Darwin mission might just be powerful enough to sense the presence of life on other worlds.

But for now, Earth remains the only place we know of where there’s life. Now that is an interesting fact!

13 Gold Medal-Worthy Olympic Stories

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In our book, it takes more than athleticism to become a true Olympic hero. Whether they were saving lives on the way to the podium or somersaulting with one leg, these athletes deserve infinite points for style. Some of them lost big-time, but all of them won our hearts.

1. THE WEIGHTLIFTER WHO BEEFED UP AT A JAPANESE INTERNMENT CAMP

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A scrawny, asthmatic child, Tamio “Tommy” Kono developed his weightlifting physique in the most unlikely of places—a Japanese internment camp. During World War II, he and his family were forced from their home in San Francisco and moved to a detention center in the California desert. For three and a half years, they endured brutal conditions along with other Japanese immigrants. Although the situation was terrible, the climate wasn’t. The desert air agreed with Kono’s lungs, and he started lifting weights to pass the time.

After the war, Kono kept training, and within a decade, he was the linchpin of the U.S. national weightlifting team. Despite his family’s detention, he proudly lifted for the Americans. Using his freakish ability to raise and lower his weight quickly, Kono helped the team fill gaps in its roster. During his career, Kono lifted competitively at weights ranging from 149 to 198 pounds. To bulk up, he’d devour six or seven meals a day; to slim down, he’d “starve” himself with three meals a day. He won his first gold medal as a lightweight during his Olympic debut in 1952, his second as a light heavyweight in 1956, and then a silver as a middleweight in 1960. All in all, he set seven Olympic records and 26 world records. Plus, he went on to become Mister Universe three times. Not bad for a boy who’d once been a 105-pound weakling.

2. RIDING TO GLORY WITHOUT THE USE OF HER LEGS

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In 1944, Danish horseback rider Lis Hartel contracted polio while pregnant. Although the illness left her almost totally paralyzed, she gave birth to a healthy baby girl. She also kept training for her event—equestrian dressage. By 1947, she was riding again, even though she couldn’t use the muscles below her knees. Despite needing help mounting and dismounting her horse, she competed for Denmark at the 1952 Games, winning a silver medal in a sport that was almost entirely dominated by men. In an indelible image of Olympic sportsmanship, Swedish gold medalist Henri Saint Cyr helped Hartel onto the platform at the awards ceremony. In the following years, Hartel kept on riding and won another silver at the 1956 Games.

Honorable Mentions:The One-Handed Gunner: Hungarian rapid-fire pistol champ Károly Takácswas known for his steady right hand. But while he was serving in the Army in 1938, a grenade accident destroyed it. Undeterred, he taught himself to shoot with his left hand and won gold medals at the 1948 and 1952 Olympics.

The One-Legged Gymnast: At the 1904 Olympics in St. Louis, American gymnast George Eyser grabbed one bronze, two silvers, and three gold medals—all while competing with a wooden leg.

3. THE BOXER WHO TURNED DOWN MILLIONS FOR COMMUNISM

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Cuban boxer Teofilo Stevenson burst onto the heavyweight scene at the 1972 Munich Games by knocking down his first opponent in just 30 seconds. He was a force in the ring, and commentators often joked that the “honor” of facing him should go to the loser—not the winner—of previous matches.

After Stevenson cakewalked his way to the gold in 1972, boxing promoters clamored for the Cuban to go pro, but he resisted. He believed passionately in the Cuban Revolution and preferred to fight on behalf of his country. After he nabbed another gold at the 1976 Montreal Games, promoters became even pushier. Stevenson passed up millions of dollars and was hailed as a national hero for his convictions. Then he picked up his third straight gold in 1980, at age 28. After retiring, Stevenson worked as a boxing consultant in Cuba, earning about $400 a month. When asked about all the money he turned down, he often replied, “What is $1 million against eight million Cubans who love me?”

4. THE HUMAN TORPEDO GETS TO KEEP HIS DAY JOB

Although professional athletes can compete in certain Olympic events today, the modern Games were founded on the purity of amateurs competing solely for the glory. However, this often forced star athletes out of the competition just for taking money to make ends meet. Legendary track-and-field champion Jim Thorpe, for example, lost his amateur status for earning $35 a week in minor-league baseball games.

Italian gymnast Alberto Braglia’s “professional” adventures were even more pitiable. After winning the all-around gymnastics gold at the 1908 Games, Braglia hit upon hard financial times. So, he turned to the place best-suited for small, athletic fellows—the circus. Performing as the Human Torpedo, Braglia delighted audiences across Europe with his daredevil stunts. In the process, he broke his shoulder and several ribs.

Irked by his stint in the circus, Italy’s governing body for gymnastics declared that Braglia had forfeited his amateur status. Just like that, his Olympic days were over. Fortunately, cooler heads realized that being a human torpedo wasn’t quite the same as being a professional gymnast, and Braglia regained his amateur status in time for the 1912 Games in Stockholm. There, the Italian wonder picked up two more gold medals. After the Games, he returned to the circus, where he enjoyed a long and successful career.

5. LOSING A RACE TO SAVE A LIFE

At the 1988 Games in Seoul, Canadian sailor Lawrence Lemieux was moving along at a quick clip, even though the seas were exceptionally rough. About halfway through the race, he seemed to have a firm grip on the silver medal when disaster struck.

Lemieux heard the cries of two Singaporean sailors competing in a different event nearby. One of them was clinging desperately to his boat, which had capsized under the six-foot waves. The other had drifted 50 feet away, swept off by the currents. Instead of staying in his race, Lemieux set course for the sailors and pulled them out of the water. His hope for a medal all but dashed, Lemieux waited for rescue boats to arrive. By the time they did, he’d fallen to 23rd place. But Lemieux’s bravery did not go unrewarded. The Olympic committee gave him the Pierre de Coubertin medal, a special award for sportsmanship.

6. BEARING THE WEIGHT OF A NATION ON A BROKEN KNEECAP

The Japanese men’s gymnastics team won gold at every Olympic Games from 1960 to 1972. So when the 1976 Games began, capturing a fifth straight gold was a matter of national pride.

Things started to come apart, however, when gymnast Shun Fujimoto felt something pop in his leg during the floor exercise. He knew he’d broken his kneecap, but hesitated to tell his coaches for fear of being pulled from competition. Knowing that his team needed every tenth of a point to win, Fujimoto decided to downplay the injury. He dusted himself off and hopped on the pommel horse, scoring a 9.5 despite the searing pain in his knee. Fujimoto later credited his injury with helping him to focus, because he knew the slightest error could have caused permanent damage. “I was completely occupied by the thought that I could not afford to make any mistakes,” he said.

Following the pommel horse was Fujimoto’s strongest event—the rings. For his dismount, he flew through the air in a triple-somersault and made a near-perfect landing with clenched teeth and tears in his eyes. The judges awarded him a 9.7, a personal best. After sticking the landing, Fujimoto collapsed in pain. Even then, he only withdrew from the competition after doctors told him he would risk permanent disability by continuing. Fujimoto’s teammates rallied around their friend’s gutsy performance and edged out the Soviets for the gold.

7. CASSIUS CLAY TOSSES HIS MEDAL INTO THE OHIO RIVER

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Before Cassius Clay became Muhammad Ali, he was a cocky 18-year-old boxer at the 1960 Games in Rome. His masterful performance in the ring won him the gold, but his friendliness and chatty demeanor won him the hearts of journalists. Hoping to capitalize on Clay’s loose tongue, the Soviet press tried to bait him into talking trash about America. One Soviet reporter asked him how he felt about being barred from certain restaurants back home, and Clay quickly responded, “Russian, we got qualified men working on that problem. We got the biggest and the prettiest cars. We get all the food we can eat. America is the greatest country in the world.”

After Clay returned home to Kentucky, he proudly wore his gold medal around his neck. But his American pride didn’t last long. In Louisville, a whites-only restaurant refused to serve him, and a white gang made the mistake of trying to attack him. After the incidents, the medal lost its luster for Clay. According to popular legend, he reacted by abruptly chucking it into the Ohio River. Four decades and one Civil Rights movement later, the Olympic committee gave Ali a replacement medal during the 1996 Games in Atlanta.

8. SLOW AND STEADY, WITH A BREAK FOR WINE

While planning the first modern Games in Athens in 1896, French historian Michel Bréal wanted to come up with an event that linked the competition to its ancient roots. He suggested a footrace that was the distance from Athens to Marathon, because a messenger had once supposedly sprinted between the two cities to spread news of a Greek military victory. The Greek people were captivated by the notion of a race with such strong ties to their country’s history, and they become obsessed with dominating the event.

While the other nations barely prepared for the competition, the marathon-crazed Greeks held two qualifying trials to choose their entrants. Except for the Greek runners, only one other contestant had run a full marathon before the Olympic Games. On the day of the race, the lack of proper training quickly took its toll. By the halfway point, runners started dropping like flies.

After nearly three hours, fans at the finish line learned that a Greek runner named Spyridon Louis had taken the lead, despite stopping along the way for a glass of wine. Greece’s Prince George and Crown Prince Constantine got so excited that they joined Louis for his last surge to the finish line. Louis, a peasant farmer, quickly became a national hero, and his name even entered the Greek vernacular. The term egine Louis, which translates as “become Louis,” is still used to mean “run quickly.”

9. THE HURDLER WHO MADE HISTORY FOR MUSLIMS, AFRICANS, AND WOMEN

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Talk about Cinderella stories. After spending her childhood running through the streets of Casablanca, Morocco’s Nawal El Moutawakel used her speed to earn a track scholarship to Iowa State University, where she won four individual Big Eight titles. In 1984, she became the only woman on the Moroccan team at the Los Angeles Olympics.

Moutawakel blew away her competition in the 400-meter hurdles, handing Morocco its first gold medal. At the same time, she also became the first Muslim woman to win a gold medal. As she ran her victory lap with a large Moroccan flag in hand, her elated countrymen back home poured into the streets of Casablanca in the middle of the night.

As a national hero, Moutawakel has used her celebrity to help other women in sports. Although Morocco largely supported her career, she knew women in other Islamic countries weren’t so lucky. One of her greatest triumphs has been organizing a women’s 10K race in Casablanca, which now draws more than 27,000 participants. As Morocco’s Minister for Youth and Sports and a major player in the International Olympic Committee, Moutawakel led the task force that chose London as the site for the 2012 Games. She has summed up her triumphs by saying, “My athletic race was the 400-meter hurdles, but it has been a metaphor for my life … You have to get over the hurdles and keep running.”

10. BRAZIL’S LONG AND WINDING PATH TO AN OLYMPIC EMBARRASSMENT

For the Brazilian team, getting to the 1932 Los Angeles Games was an Olympic trial all its own. The Brazilian government was bankrupt, and it couldn’t afford to pay for the team’s expenses. So the athletes traveled via coffee barge, stopping at ports between Brazil and Los Angeles to peddle roasted beans. All they needed was to sell the 50,000 bags on board.

Unfortunately, the team made only $24. At the time, the tax to enter the United States was $1 per person, meaning only 24 members of the squad were able to leave the ship. The other 45 teammates had to set sail for the Pacific Northwest to try to unload the rest of the coffee.

Sadly, the athletes who did make it to the Games didn’t fare particularly well. After losing to Germany 7-3 in water polo, the Brazilian team jumped out of the pool and started pounding on the referee. The police pulled the Brazilians off the battered official, and the team was disqualified from the rest of the Olympics.

11. THE BABE WHO RAN CIRCLES AROUND THE COMPETITION WHILE PLAYING THE HARMONICA

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When the Los Angeles Olympics rolled around in 1932, a 19-year-old typist named Mildred “Babe” Didrikson faced an unusual problem. The rules dictated that an athlete could only enter three track-and-field events, and Didrikson had qualified for five. So, she simply picked the ones in which she already held world records—javelin, 80-meter hurdles, and the high jump.

Her first event didn’t get off to an auspicious start. The javelin slipped from her hand and tore the cartilage in her right shoulder. For most athletes, that would have meant instant defeat, but Babe’s compromised throw sailed more than 143 feet and set a new world record. Two days later, Babe set another world record in the 80-meter hurdles. She looked poised to sweep her events, but was disqualified in the high jump competition for diving headfirst over the bar, which was illegal at the time. She had to settle for silver.

Didrikson had an outsized personality to match her athletic prowess. Reportedly, she’d greet her opponents with the taunt “Yep, I’m gonna beat you.” And during training sessions for the Los Angeles Games, she would irritate her teammates by literally running circles around them while playing her harmonica.

Babe’s sports dominance didn’t stop with track and field. In 1935, she picked up golf, and by 1950 she had won every available women’s title in the game. She’s still considered one of the greatest golfers of all time, male or female. Never humble, Didrikson wrote in her autobiography, “My goal was to be the greatest athlete who ever lived.”

12. SOVIET SISTERS OR COMMUNIST BROTHERS?

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No one ever questioned the athletic prowess of Tamara and Irina Press, two Russian sisters who were unstoppable in track and field. People did question their gender, though.

At the 1960 Games in Rome, the Presses became the first sisters to win gold at the same Olympics. Tamara set an Olympic record in shot put, and Irina won the 80-meter hurdles. At Tokyo’s 1964 Games, they were even more dominant. Tamara won the gold in both discus and shot put (beating her own record), while Irina won the first women’s Olympic pentathlon.

Given their hulking stature and masculine features, rumors started to spread about their gender. Rivals derisively labeled them “the Press Brothers,” but the whispers turned into shouts after the International Amateur Athletic Federation announced that it would begin gender testing at the 1966 European championships. Both sisters promptly withdrew from the event and disappeared from competitive track and field.

The Western media gleefully interpreted their retirement as a tacit confession. A Soviet spokesman dismissed the accusations as jealousy and claimed the sisters had stayed home to care for their ailing mother. The truth remains an Olympic mystery.

13. A HEARTWARMING MOMENT IN JAPANESE SPORTSMANSHIP

At the 1936 Berlin Games, Japanese pole vaulters Shuhei Nishida and Sueo Ōe tied for second place. The teammates were offered the opportunity to have a jump-off for the silver medal, but the two friends declined out of mutual respect for one another. For the purposes of Olympic records, Ōe agreed to the bronze while Nishida took the silver.

Upon their return to Japan, the teammates came up with a different solution. The pair had a jeweler cut their medals in half and fuse them back together, creating half-silver, half-bronze pendants. The “Medals of Friendship,” as they’re now known in Japan, are enduring symbols of friendship and teamwork.

How do I know if I’m dehydrated? The symptoms you should never ignore

It’s not summer yet, but much of the country will be experiencing a heat wave this summer.

When it’s so hot, staying hydrated is key to staying healthy. Dehydration is a serious health concern. Last year, a study published in the American Journal of Public Health found that more than half of all children and adolescents in the U.S. aren’t getting enough water.

“People don’t realize the amount of fluid they can lose in the heat, or while exercising,” explained Michael F. Bergeron, Ph.D., and president and chief executive officer of Youth Sports of the Americas. “And it’s important to note that your hydration needs are very individual,” continued Bergeron.

This health issue is more serious than you might think and could land you in the hospital.

How much liquid do we need each day? It depends. Here are a few signs you might be dehydrated and tips to stay healthy all summer long.

1. Increased thirst and a dry or sticky mouth

“If you feel thirsty, you’re already dehydrated,” explained Dr. Laura Goldberg of Cleveland Clinic Sports Health. The easiest remedy is to start drinking water (and beverages with electrolytes) as soon as you notice this, but try not to let yourself get to this point.

The best way to prevent this from happening is to meet your daily hydration needs, for women, the National Academy of Sciences recommends 2.7 liters of water a day (about 11.4 cups), and for men, 3.7 liters (15 cups). Try to drink more water if you’ve spent excessive time in the sun, or exercising.

2. Signs of fatigue, confusion or anger

Studies have found that mild levels of dehydration can affect your mood and cognitive functions. This is especially common in the young or elderly, who may seem less alert, or forgetful.

A study from the University of Connecticut’s Human Performance Laboratory found that even mild dehydration can alter a person’s mood, energy and ability to think clearly. The researchers defined mild dehydration as an approximately 1.5 percent loss in normal water volume in the body — and the adverse reaction is the same whether you’re exercising or sitting still.

3. Dry eyes or blurred vision

“When you’ve been exercising for a long time, you’re sweating and your overall body fluid goes down — this can result in dry eyes or blurred vision,” said Goldberg, who also noted that any part of the body that is normally moist is going to feel dry or irritated.

“Monitor your hydration levels and make sure you’re drinking throughout any form of exercise,” she explained further.

4. Headaches or disorientation

Dehydration can result in a headache or migraine, light headedness or delirium. “I’ve seen marathon runners running in zigzags because they’re dehydrated. You can’t make decisions and feel delirious,” elaborated Goldberg.

“You may also experience weakness, dizziness, or nausea, because the body doesn’t have enough fluid to send to other parts of the body. This could also result in heat exhaustion. You can collapse if you don’t stop exercising and cool down,” warned Bergeron, who also added that these specific symptoms can also be signs of over hydration, so be aware of how much you’re drinking.

5. Muscle cramps

“If you’ve been exercising, it’s natural for your legs to feel tired, but if it’s more than that and you’re experiencing muscle cramping, that’s a serious sign of dehydration,” Goldberg explained. This is because of the loss of water and salt in the body — you also might experience tightness in your muscles, instead of cramping.

“Wandering and progressively widespread muscle cramping is a certain clue of a sodium deficit and dehydration in the fluid spaces surrounding certain muscles,” Bergeron elaborated. “But don’t confuse it with an overworked muscle which would just affect a small area.”

To prevent this from occurring, it’s important to drink sports beverages that contain sodium, or snack on salted pretzels or low-fat cheeses. The sodium helps your body to re-hydrate and retain the water.

6. Lack of sweat

According to Goldberg, this is one of the more serious signs of dehydration. It means your body is in dire need of water. Though, on the other hand, Bergeron notes that more likely it may be a sign of overheating or heat stroke — though either can occur in the presence of continued sweating. Either way, it’s crucial to cool down rapidly if you’re not sweating anymore.

7. Dark urine

“Straw-colored or light yellow urine means you’re properly hydrated. If your urine is dark, or if there’s blood in your pee, you need to stop exercising immediately,” warned Goldberg. Notably, perfectly clear urine may mean that you are over-hydrated.

8. Fever

“Dehydration can lead to hyperthermia and a fever-like symptoms (e.g. chills) because over-heating can alter your body’s normal temperature ‘set point,’” explained Dr. Goldberg. Excessive overheating is an urgent red flag. Stop exercising immediately, take an ice bath and hydrate.

9. Shriveled and dry skin

If your skin is hydrated, it will appear doughy. If you’re dehydrated, your skin will lack elasticity and won’t bounce back. “If you pinch your skin and it appears thin and doesn’t melt back onto your body quickly, you’re dehydrated,” said Goldberg.

Some key things to remember when exercising in the summer is that the longer you’re working out, the more water you need. Also, plain water is good for you, but a combination of water, electrolytes and sodium is really the best way to stay hydrated.

It’s also crucial to understand that hydrating properly isn’t 100 percent preventative, if you’re working too hard and too long in the summer heat, you can still overheat no matter how much water your drinking. So be aware of your body, and stop what you’re doing if you notice any of these symptoms.

What Does a Purple-Painted Tree or Fence Post Mean in Texas?

If you’re an avid back-country explorer or typically find yourself going off the beaten path, take special care to notice purple trees and fence posts. What may seem like irregular oddities are actually visual ‘No Trespassing’ signs.

This phenomenon began in Arkansas in 1989 as a way for property owners to signify their divide between public and private land for others. Soon, nine other states adopted the same token purple tree. Texas joined the ranks in 1997.

The official law states that landowners, however, had to put up a sign detailing what the purple paint means in addition to painting the area. So if signs are required, why use paint, too?

Well, as Jonathan Kennedy said, “The reason the Texas legislature did that is they were trying to keep landowners from constantly having to replace signs. In Texas as we know, people like to take target practice at signs so they are having to replace them frequently.”

This strategy simply keeps landowners from constantly having to replace signs, and the color purple was chosen because it is visible to even colorblind individuals. So, next time you spot purple paint in Texas on a fence post or tree, take caution in crossing that line because you’re then venturing onto someone’s private property.